How can i change the color of a material created with the PBR addon
The thing with PBR is: it tries to be physically accurate. That's why you don't have a RGB input in this setup but a blackbody converter node.

Blackbody converts color temperature (measured in kelvin) to RGB values.
You can look at the Wikipedia page to see which color corresponds to which kelvin value.

if you don't need to be physically accurate, you can just unconnected the blackbody node and set the color directly in the emission shader.